7 Most Common Reasons Furnaces Stop Working Properly

When the hot air stops coming out of the vents, an HVAC specialist may need to inspect the furnace. There is a variety of common issues that may require repair, including slipped blower belts and cracked heat exchangers. Understanding these causes may help homeowners make more sense of their furnace repair bill.

1. Dirty Filters

Dirty filters do not always lead to repairs. However, they can impact the efficiency of the furnace. When the filter is dirty, the furnace needs to work harder to generate heat and blow air through the vents. This puts more stress on the system, increasing the risk of any of the following issues.

2. Cracked Heat Exchanger

One of the worst issues that a homeowner can discover is a cracked heat exchanger. The heat exchanger is the main component of the furnace, as it is responsible for heating the air. When this component becomes cracked, the furnace may stop producing hot air.

The cost of replacing the heat exchanger may not be cost-effective compared to replacing the furnace. If the furnace is more than a few years old, the most economical choice is typically to replace the furnace instead of replacing the heat exchanger.

3. Pilot Control or Ignition Problems

Issues with the ignition may keep the furnace from turning on or reduce the heat output of the appliance. Luckily, hiring furnace repair Oshawa for one of these issues may not cost a lot. Replacing the pilot light or solving an electric ignition issue does not typically require a lot of labour or supplies.

4. Thermostat Malfunctions

When the thermostat stops working properly, homeowners may set the temperature higher or lower than normal, increasing their heating bills or decreasing their comfort.

While an issue with the thermostat may not require repairs to the furnace, HVAC specialists can properly install new thermostats for precise control over the temperature in the house.

5. Worn Out Ball Bearings

Worn out ball bearings can create a scraping sound. When homeowners hear this sound, they should shut off their furnace and contact an HVAC professional.

The worn ball bearings scraping on the inside the furnace can create additional damage. If the problem is ignored, the damage may become too severe, requiring the homeowner to replace the furnace.

6. Clogged Air Ducts

When the air ducts become clogged with debris and dust, the furnace becomes less efficient. Like a clogged filter, the blockage can place additional stress on the furnace, shortening its service life.

One sign of clogged air ducts is frequent cycling. When the furnace constantly turns on and off, the air ducts or filter may be too clogged.

7. General Mechanical Issues

Besides the issues discussed, there are dozens of other mechanical issues that may occur. These mechanical problems are often categorized by a loud sound. Homeowners may hear high-pitched squeals, rattling, or rumbling noises.

These sounds may indicate that there is an oil leak, worn parts, loose screws, or a variety of other issues that require inspection by an HVAC expert.

The bottom line is that any furnace problem should be addressed by a qualified professional. Other than replacing a burnt-out pilot light and changing the filter, the remaining maintenance tasks are best left to the professionals.